Find your DAC under "Playing Now" in the left tree view in Media Center. If you don't see it in the tree, wait a bit - sometimes it takes a bit for it to broadcast it's existence. If it still doesn't show up, try power-cycling the DAC.

Right-click on your DAC and select "Associate with DLNA Server".

Choose the "Audiophile 24-bit DAC" choice from the list.

Normally you shouldn't need to modify the items under "DLNA Controller Options".